In the network that is constructed to transmit or receive information by using the applicable LAN (Local Area Network) in the plural number of terminal devices connected to the LAN, there may be cases where the existence or non-existence of the communication should be confirmed after the communication has been conducted.
For example, there may be cases where we want to confirm whether a network crime has been conducted or not from the inside of LAN network or the external network connected to the LAN network (e.g., Internet) and we want to obtain an evidence that the communication has been conducted (e.g., the evidence of electronic commercial transaction).
As a method to solve such problems, a method to provide software using the GUI (Graphical User Interface) for information recording only in each terminal device has been adopted. However, this has created complicated works when confirming the recorded information after the communication has been conducted.